Matsuura Research Group

Research Topics

  • Cryptography
  • Cybersecurity
  • Anonymous communication system
  • Economics of information security

Fingerprinting Attack against Tor Anonymous Communication System


Tor anonymity system drew the social attention since it was used in the communication related to Arab Spring, the remote-control virus incident, and so on. We invented a robust fingerprinting attack against Tor; when the network condition allows, the success rate of our attack is higher than 80 percent. We examined features of countermeasures, and found anonymous communication is difficult if favorite homepages are less than 20. With the help of machine learning, the attack can be effective even when the number of possible homepages is around 50. Our further studies include (1) the robustness of the attack with respect to noise-based defense and (2) anonymity reduction by active attacks.